Restoring mechanism for adding machine indexing means



May 20, 1958 R. w. PlTMAN RESTORING MECHANISM FOR ADDING MACHINEINDEXING MEANS 4 Sheets-Sheet 1 Filed Nov. 3. 1954 Q lNl/ENTOR RICHARD wp/ TMAN d ATTORNEY May 20, 1958 R. w. PITMAN ,83

RESTORING MECHANISM FOR ADDING MACHINE INDEXING MEANS Filed Nov. 3, 1954w 4 Sheets-Sheet 2 I INII/ENTOR R/CHARDWP/TMAN AT TORNEV May 20, 1958 w,PITMAN 2,835,441

RESTORING MECHANISM FOR ADDING MACHINE INDEXING MEANS Filed NOV. 3, 19544 Sheets-Sheet 3 RICHARD WP/TMAN ATTORNEY y 20, 1958 R. w. PITMAN2,835,441

RESTORING MECHANISM FOR ADDING MACHINE INDEXING MEANS Filed Nov. 3, 19544 Sheets-Sheet 4 i4 /0/ 2 jjjjj;;1j r 1 I Z; 417 80 i 50 50 4f 1 "m m a;

' CAM 0 3O 60 90 I20 I50 I80 ZIO 240 270 300 330 TYPEBARS N REGISTERRACKS DISENGA T TA O INVENTOR WP/TMAN CARRYOVER 4% PRINTINQ A TTORNEVerated line. 'operated since the usual A. (1-D. C. electric motors re-RESTORING MECHANISM FOR-ADDING MACHINE INDEXING MEANS Richard W. Pitman,Laverock-Hillcrest, Pa.,-'as'signor to Underwood Corporation, New York,N. Y., a corporation-of Delaware Application'November 3, 1954, SerialNo. 466,645

6 Claims. (CL 235'---60) This invention relates to improvements in a-ten key adding machine, and more particularly to improvementsforsimplifying the construction of'such a machine.

Ten-key addingmachines are-wellknown-andhave-been "on the market formany years with many companies marketing inexpensive machines which,generally, are

stripped down versions of their higher priced motor-p- Such inexpensivemachines are all manually quired to drive the machine are noteconomically possible at the competitive price level. The machinedisclosed in this application is particularly designed to be powered byan inexpensive A. C. motor of the shaded pole type used for fans andsimilar light duties and may be constructed mainly of simple,automatically producible 'parts.

'It is a major object of this invention to devise a ten keyadding-machine of a minimum number of parts, most of which are metalstampings.

It is also an object of this invention to produce an adding machineindexing mechanism which is simple in design and requires a minimum offorce to operate with no peak load points.

Another object is the inclusion of a pin carriage restoring mechanismwhich maybe locked in a disabled position for one cycle to provide arepeat entry of an item whether the repeat key remains operated during acycle or not.

Other objects will be in part obvious or pointed out in the followingdescription and accompanying drawings of a :preferred embodiment of theinvention.

In the drawings:

Figure 1 is a left elevation of the mechanism of the machine,

Figure 2 is a vertical section taken on a front to rear line through themachine,

Figure 3 is a left side view of the pin carriage restoring and itemrepeat mechanism,

Figure 4 is a view of a portion of Figure 3 showing the parts inoperated position,

Figure 5 is an isometric view of the mechanism of Figure 3, I

Figure 6. is a plan view of the motor drive and the cycling clutchcontrols therefor,

Figure 7 is an isometric view of the register engaging cams and the zeroeliminating control for total printing,

Figure 8 is a view showing a part of the total signal printingmechanism,

Figure 9 is a rear view of the amount indexing mechanism,

Figure 10 is a sectional view showing the numeral key connections to theescapement and pinv setting members,

Figure 11 is a front elevation of the platen,

Figure 12 is a right side view showing the platen printing stop, and

Figure 13 is a diagram showing the timing of the operating members.

2 General description The disclosed adding machine is of the well knownten key type and is driven by a rotary drive shaft cyclically energizedby an electric motor and driving a group of cams. Numerical items areset up by the ten numeral keys in settable pins of a travelling pincarriage controlled in its travel by a key operated escapement. The setpins of the pin carriage limit, during a cycle, the travel of alignedtype bars to present type at a printing line. A platen, a paper tapearound the platen and an inked ribbon are then swung against the typebars to record the set up item on the tape and a register is engagedwith a toothed portion of the type bar to enter the set up values in theregister during the return of the bars to a home vposition. When thetype bars are fully restored, the pin carriage is returned to a homeposition to reset any set pins in preparation for the succeeding entry.

The machine is also operable to print the total of accumulated amountsby engaging the register with the type bars prior to initial movement ofthe bars and utilizing the tens'carry mechanism to arrest movement ofthe type bars at a number corresponding to that originally in the reginboth item or total printing operations, the platen mechanism'is sodesigned that the pressure exerted against the individual type bars willbe substantially constant irrespective of the number of bars againstwhich the %platen presses. This is accomplished by mounting the platenin its frame at a'slight angle from the printing line and arresting oneend of the platen near the end of the printing stroke to effect aseriatim pressure on the bars.

More specifically, the operating mechanism is mounted on a frameworkcomprising a base plate 15, Figure 1, resiliently mounted on feet 16 andsupporting right and left sidepla'tes 1-8 and 19, respectively, see alsoFigures 2 and-11. The base 15 also supports a shaft 21, to be laterdescribed, in bearings 22.

Cycling mechanism The machine is driven by a rotary cycling mechanism'engageable for one cycle of operation by motor keys in the keyboard.Referring to Figure 6, a shaft 24 of a motor, not shown, mounted onright side plate 18 has a "gear 25 secured thereto to drive a gear 27rotatable in side plate 18, A shaft 28 is slidably' and rotatablymounted in a bearing 30 in side wall 19 and passes through the open axisof gear 27. Shaft 28 has a collar 31 secured thereto and also a clutchmember 33 sl'idabl'e thereon but prevented from rotating on the shaft bya pin 35 in shaft 28 engaging in hole 36 of'the member 33 with a spring34 between collar 31 and clutch member 33 to yieldably hold member 33 tothe right. Clutch member 33 and the hub. of gear 21 have mating teethformed thereon toprovidedriving engagement between these parts whenshaft 28 is: moved to the right.

Secured: to: the left end of shaft 28 outside plate 19 are a-groovedcollar38i and a gear 39. Gear 39meshes with *a. large gear 41 rotatableon a stud 42 secured in left side also Figures 1 and 2, each of whichkeys has a lug engageable with ears on a rockable plate 50 pivoted inspacer bars 51 of the keyboard plates to be later described; see alsoFigure 10. Plate 50 has a rearward extending arm 53 which will whenplate 50 is rocked by operation of a key, engage a cam edge of a. triplink. 54

mounted outside of plate 19 on a stud 55 in plate 19.

A spring 57 on stud 55 presses the forward part of link 54 against sideplate 19 which has a slot therein to allow the cam edge of link 54 topass through into contact with arm 53 of plate 50. The rear end of link54 is bent outwardly and engages in the groove of collar 38 with thebend line serving as a rocking fulcrum on plate 19. A bent off ear 58 oflink 54 is normally engaged in a notch of ring 44 to hold gear 41 in ahome position. When any motor key is operated, link 54 is rocked aboutits fulcrum on plate 19 to remove ear 58 from the notch of ring 44 andto shift shaft 28 rightwardly to engage the teeth of member 33 and gear27. The right end of shaft 28 when moved rightwardly is utilized toclose a switch, not shown, to energize the driving motor and therebystart rotation of shaft 28 and gear 41. As soon as gear 41 startsrotating, clockwise in Figure l, the notch of ring 44 moves away fromear 58 and upon release of the operated key, the ring 44 maintains link54 in its operated position until gear 41 completes a full revolutionand ear 58 can again drop into the notch to disconnect clutch member 33from gear 27 and de-energize the motor.

Type bars The machine is provided with a plurality of type bars 60,Figure 2, one for each denominational order, arranged for slidingmovement on a plate 61 secured between side plates 18 and 19. Each typebar 60 has at its forward end a tail 62 passing downwardly through aslot in plate 61 and an upwardly extending ear 64 to limit movement ofthe bars 60 during item entry operations. The type bars are each formedwith a rack and a notch in their upper surfaces and each has securedthereto a type bearing plate 65. A spring 66 is connected between eachtype bar tail 62 and the rear edge of plate 61 to urge the barsrearwardly but the bars 60 are normally restrained in their forwardposition by a plate 68 engaging the tails 62 and guided in slots 69, seealso Figure l, in plates 18 and 19. The rear end of plate 68 is pivotedon an arm 70 secured to shaft 21 on base 15. Another arm 72 on the leftend of shaft 21 is connected by a link 73 to a cam follower 74 pivotedon a stud 76 in side plate 19 and urged clockwise by a spring 77 intocontact with a cam 78 secured to gear 41. As may be seen from the firstline of the timing diagram Figure 13, the cam 78 during a rotation ofgear 41 will first release the type bars 68 for movement to align theirtype at the printing line and then after a short pause will release bars60 for further rearward movement until they are difierentially arrestedin a manner to be later described. During the second half of arevolution of cam 78, bar 68 will be driven forward to first return alltype bars to the 0 position and again after a short pause, to restorebars 60 to their normal forward position.

Item set up mechanism The rearward movement of type bars 60 to print andregister an item is controlled by a set of digit keys 80 and a shiftablepin carriage 81 carrying a plurality of rows of pins 82, see Figures 2,3, 9 and 10. The digit keys 80 are guided for vertical movement in slotsin an upper keyboard plate 84 secured by spacer bars 51 to a lowerkeyboard plate 85 secured between side plates 18 and 19. Each key stemof a key 80 is formed with an arm extending over an escapement bail 86,Figure 10, pivoted in the two left spacer bars 51 and tensioned upwardlyby a spring 87 with the arm of each key stem except that for the "9 keyhaving a pin setting projection passing through lower keyboard plate 85.Compression springs 88 between the plate 85 and the arm of each key stemnormally holds the keys 80 in their upper positions.

Mounted below the keyboard plate 85 on horizontal rods 89 securedbetween depending ears of plate 85, is the pin carriage 81 comprisingupper and lower plates secured together and embracing rods 89 forsliding movement of carriage 81. The settable pins 82 pass through thepin carriage plates and are frictionally held in any set position by aspring wire passing in serpentine fashion through a row of pins, by leafsprings or other suitable friction devices. Pins 82 are arranged in rowswith the pins in each row being alignable with the pin settingextensions of keys under control of an escapement mechanism hereinafterdescribed and each pin 82 when set by a key 80 has its lower end in thepath of the ear 64 of the type bar 60 with which it is aligned to arrestthe type bar 60 at the digit value corresponding to that of the operatedkey 80. A plate 92 fixed to the rear of pin carriage 81 will arrest anytype bar 60 reaching it at the 9" position and therefore it is notnecessary to set a pin 82 when the 9 key 80 is depressed. To preventrearward movement of type bars 60 for which no pin 82 has been set, abracket 93, Figures 3, 5 and 8 is secured to the left side of the pincarriage 81 to pivotally support a zero stop plate 94. Stop plate 94 inthe normal position of pin carriage 81 lies just to the rear of the ears64 of type bars 60 and is moved from in back of successive ears 64 bythe movement of the pin carriage incident to the setting of a pin 82 ina position to limit movement of a type bar 60.

The pin carriage 81 is urged to the left by a spring 90, Figure 9connected between the carriage and an arm 91 secured to and extendingleftward from the lower keyboard plate but is restrained by anescapement dog 97, Figure 9, pivoted to an ear on escapement bail 86. Aspring 98 connected between the bail 86 and the dog 97 holds the end ofthe dog under an ear 99 of bail 86 with the edge of the dog 97 just tothe right, left in Figure 9, of the edge of car 99. A rearwardlyextending portion 101 of pin carriage 81 is bent into engagement withdog 97 and is provided with notches, Figure 10, having the same spacingas the rows of pins 82 and the type bars 60. The ear 99 and dog 97 arealternatively engageable with the notched part of carriage 82 each timethe escapement bail 86 is rocked by depressionof a key 80 to provide astep by step movement of pin carriage 81 in the well known manner.

An interlock to prevent operation of a numeral key 80 during a machinecycle or operation of a motor key 45, 47 or 48 while a numeral key isdepressed is provided in the machine. As shown in Figures 9 and 10, alever 102 is pivoted on top keyboard plate 84 and its rearward end isengaged in a slot of the trip link 54 to be rocked counterclockwise uponeach depression of a motor key 45, 47 or 48 as above set out. Theforward end of lever 102 is engaged in a slot of a key lock slide 103which is guided between the keyboard plates 84 and 85 and which willhave its right end (Figure 10) inserted under the escapement bail 86during the whole time that the trip link 54 is held rocked by a motorbar 45, 47, or 48 or by ring 44 on gear 41. Such interposition of slide103 will prevent operation of a numeral key during the entire machinecycle and, if a numeral key should be held depressed, it will preventany effective operation of one of the motor keys.

Pin carriage restoring mechanism The pin carriage 81 is normallyreturned to the right near the end of a machine cycle to restore any setpins and thus prepare the machine for entry of a new item. Referring toFigures 3, 4, and 5, a link 105 is pivotally connected between bracket93 of pin carriage 81 and an arm 106 pivoted on a post 10.7 secured tokeyboard plate 85. Also slidably pivoted on post 107 is a bail 109having a shoulder 110 normally engaged between a forward ear 111 and arearwardly bent up ear 112-on arm 106. A spring 114 connected betweenarm 186 and bail 189 normally maintains shoulder 11% against ear 112 tohold an ear 115 of bail 189 in position to be engaged near the end of amachine cycle by a cam 116 fixed tov gear 41 inside of ring 44.Engagement of the cam 116 with ear 115 of bail 109 will swing bail 189to engage shoulder 110 with ear 111 of arm 106 and return pin carriage81 to its rightmost position where it will be retained by escapement dog97.

During such restoration of pin carriage 81 to the right, any set pins 82will be reset to their upper ineffective position by a cam plate 118,Figure 9, secured to side wall 18 under the pin carriage 81.

Should the operator make an error in setting up an item or wish to clearout a set up item for another reason without printing or entering suchamount, an error key 119 is provided. This key 119 is slidable in thekeyboard plates 84 and 85 and has a spring 120 similar to springs 88 fornumeral keys 80 to hold key 119 in its upper position. An ear of key 119is engaged by an arm of a bell crank 122 tensioned upwardly by a spring123 and having a hooked end 124.

By depression of error key 119, bell crank 122 may be pivotedcounterclockwise, Figure l, to bring its hooked end 124 into engagementbehind bar 68. During an ensuing machine cycle which may be initiated byoperation of either key 45 or 47, bar 68 is prevented from releasingtype bars 60 so there will be no printing or item entry and the onlyeffective operation will be the restoration of pin carriage 81 to itsinitial position.

Item repeat mechanism When the operator wishes to retain a set up itemfor a number of cycles as in multiplication operations, a machine cycleis initiated by operation of repeat'key 48. This key in addition tooperating the cycle trip plate 50 also rocks a lever 126 which underlieskey 48 and is pivoted on the rear pin carriage rod 89. A compressionspring 127, Figure 5, between a collar 128 fixed on rod 89 and the rightedge of lever 126 urges lever 126 to the left, right in Figure 5, tohold its left edge in contact with a pin 13,8 fixed in plate 85 adjacentto rod 89. When the lever 126 is rocked by depression of key 48, a slot131 in .lever 126 is aligned with the pin 130 and lever 126 is moved byspring 127 rightwardly in Figure 5 to retain lever 126 in its rockedposition as shown in Figure 4.

' The rear end of lever 126 underlies a tooth 132 projecting from bail199 and will, when lever 126. is rocked, raise the bail 189 so that itsshoulder 110 is above the ear 111 of arm 186. In the ensuing machinecycle, arm 106 will not be rocked by the bail 189 and the item set upwill be retained. Near the end of the movement of bail 109 in thisoperation, tooth 132 of bail 109 will strike an car 135 on lever 126 toshift the lever back to the right side, disengaging pin 130 from slot131 and so freeing lever 126 for return to its ineffective position.Restoration of lever 126 is, however, not positive and so long as key 48is held depressed, the machine willcontinue to cycle and repeatedly addthe set up amount. For the last cycle, the motor bar 45 and, if the itemis not to be entered, the error key 119, may be operated to clear outthe set up item.

Printing mechanism The machine includes a printing mechanism to make arecord of the items entered and the totals thereof but as this mechanismforms no part of the invention claimed herein, it will be but brieflydescribed. As shown in Figures 1 and 2, a platen 136 is rotatablysupported in A roll of paper tape 147 is supported on a rod 149 and thetape from the roll is passed between platen 136 and a set of springpressed eed rolls around platen 136 and below the type plates 65 andthen out to the rear of the machine. After a record is made on the tape147 by upward movement of the platen 136, the tape is stepped to therear by a detent 156, see Figure 2, which engages in the teeth of aratchet wheel on the right end of platen shaft 137 to turn the platenduring return movement of the platen frame 138.

An inked ribbon 159 passes between two tape spools 160, one on each sideof the machine and rotatable in lower extensions of platenframe 138 withthe ribbon passing over the platen 136 between the type plates 65 andthe paper tape 147 so that pressure of the tape 147 against the inkedribbon and type bars 65 will record on the paper. A shaft 169 with apair of pawls 173 and 168 thereon is pivotally mounted in plates 18 and19 below the ribbon spools 168 and is spring held in a set position byan over center spring 172, Figure l. The other end of spring 172 issecured to a tape follower arm 174 which acts to reverse the position ofshaft 169 when the tape on the left hand spool nears exhaustion or thecapacity of the spool and hence reverse the direction of drive of thetape 159 across the platen.

As shown in Figure 11, the right end of platen 136 is slightly higher inframe 138 than is the left end. An adjustable stop 145 first arrests theright platen frame 138 as the right hand type bars 60 are contacted byplaten 136. The remainder of the bars 60 will be contacted by platen 136through a twisting of the platen frame 138 by the drive from arm 142 andmovement of platen 136 will be substantially .a rocking motion so thatall type will be contacted with about the same pressure giving evenprinting irrespective of the number of type being contacted by theplaten 136.

Item entry registration A register mechanism is provided to sum up theitems entered by key 80. The frame for the register comprises a U shapedmember 178, Figure 2, pivoted in the side frames 18 and 19 by ears 179secured to frame 178. Secured to the bottom of frame 178 is a bracket181 having forwardly extending arms in which is mounted a shaft 182rotatably supporting a plurality of register wheels 183. Frame 178 isrockable about its pivots 179 to engage register wheels 183 with racks185 out in the upper surfaces of type bars 60 to enable rotation ofwheels 183. A slotted leaf spring detent 186 is secured to the upperpart of frame 178 and is bent into engagement with the teeth of wheels183 to yieldably hold the Wheels 183 in any set position.

A tens transfer mechanism to move the next higher denomination wheel 183one additional step whenever a wheel 183 passes from its 9 to its 0position is provided in frame 178. The tens carry mechanism comprises,for each order, a slide 187 and a spring 189. Each slide 187 is slidablein slots in frame-178 between a pair of wheels 183. The slides areslidably retained in the slots of frame 178 by a stop plate 188 at the,bottom and a bracket 198 secured to the top of frame 178 and are urgeddownwardly by their springs 189. Normally, the slides are retained intheir Figure 2 positions by the engagement of a shoulder 191 on theslides with stop plate 188 until during the rotation of a numeral wheel183 between its 9 and 0" positions, a wide tooth 193 of a wheel contactsa cam surface 194 on slide 187 to move the bottom end rearwardly off ofstop plate 188 permitting spring 189 to move the slide 187 downwardlyuntil a nose 195 at the top of the slide contacts a restoring bail 196.When bail 196 is moved downwardly to permit slide 187 to move to itslowest extent, a tooth 199 extending to the left from slide 187 willengage a tooth of the next higher denominational wheel 183 to move itone space. If another slide 137 is released by such movement of a wheel183, it will be free to move downwardly and transfer to the next higherwheel 183.

' The restoring bail 196 is secured to a shaft 201) pivoted in arms 281secured to frame 178. On the left end of shaft 280 is a cam follower arm283, Figure 1, tensioned clockwise by a spring 2114 around shaft 286into contact with a cam 285 secured to gear 4-1. The movement of bail196 by cam 285 is as shown in the fourth line of l Figure 13 whereinslides 187 are shown held in their restored positions until the registerwheels 133 are engaged with racks 185 after which the slides are reedfor movement to a set position by the Wheels 183 which move from their 9to position. After the wheels 183 are removed from racks 185, the bail196 is lowered to permit the slides 187 to drop to their lower positionfor carryovers after which bail 196 is again raised to restore slides totheir reset positions wherein their shoulders 191 are resting on stopplate The double levels in the restored and set slides positions are tocompensate for the movements which frame 173 may make in engaging anddisengaging register wheels 183 with racks 185 and do not represent anyeffective movement of bail 196.

Register engaging mechanism The register wheels 183 are rocked intoengagement with the racks 185 by the mechanism shown in Figures 211 onfollower 208 passing through a hole therein is a cam follower 212slidable on stud 76 and urged toward side wall 19 by a compressionspring 213. Cam follower 288 is held counterclockwise at the homeposition of gear 41, Figure l, by a cam 215 secured to gear 11 to holdcam follower 212 free of its cams to enable easy shifting of follower212 on stud 76. During a machine cycle, cam follower 208 does not followits cam 215 and is controlled by follower 212.

Cam follower 212 is axially shiftable as above noted to engage either oftwo cams, an adding cam 216 and a total cam 217, both cams being securedto boss of gear 41 with a slotted blocking plate 219, Figure 1, betweenthem. Blocking plate 219 is not shown in Figure 7 in order that theoutline of cam 216 will not be obscured but lies between the two cams216 and 217 with its slot aligned with the nose of follower 212 as shownin Figure 1. For adding cycles, follower 21?. engages cam 216 andthrough its connection to follower and link 2117 will shift the registerframe 178 as shown on the second line of Figure 13, that is, to engagethe register wheels 183 with racks 135 during the return move ment oftype bars 68 between their set and their 0 positions. Such registerengagement will enable the number set up on type bars 60 to be enteredinto wheels 183.

When it is desired to print the total of the entered items, the totalkey 47 is depressed. This key 47 is formed with an inclined ear 229,Figure 7, and when depressed will, in addition to starting a machinecycle as previously described, swing an arm 221 about its pivot inplates 85. Arm 221 abuts the right edge of cam follower 212 and when key4'7 is depressed will move follower 212 to the left through a slot inblocking plate 219 into engagement with cam 217. During the ensuingcycle, cam 217 will cause the register wheel 183 to be engaged withracks 185 in the total timing shown in the third line of Figure 13, thatis, during the rearward stroke of type bars 6 3 from their 0 toward the9 position. Blocking plate 219 prevents cam follower 212 from movingback to the add position despite a.

release of total key 47 before the end of a machine cycle.

During such rearward movement of type bars 60, the wheels 183 arerotated reversely until their wide teeth 193 are individually engaged bythe lower edges of cam surfaces 194 on slides 187 which engagementarrests the wheels 183 at 0 and type bars 63 at a position correspondingto the initial setting of wheels 183 as is well known. The platen 136will thereafter be driven as set out above to print on tape 147 the itemtotal.

Total key 47 when depressed for a total cycle causes the release of allof the type bars 6t and releases a symbol bar 233, Figure 8, to align atotal signal type for printing. As shown in Figures 1 and 8, blockingplate 94 for type bars 60 is pivoted on bracket 93 of pin carriage 81and underlies key 47 so that depression of total key 47 will lift theforward end of plate 94 and permit free rearward movement of type bars60 during the machine cycle.

The symbol type bar 223 is normally held by a plate 224 pivoted in sidewalls 13 and 19 and pulled into engagement with an ear on symbol bar 223by a spring 225 to normally hold the bar 223 against movement during amachine cycle. When plate 94 is operated by total key 47, the forwardedge of the plate contacts an ear on plate 224 to lift the plate 224away from bar 223 which will during the ensuing cycle, follow restoringbar 68 until the front edge 227 of a slot in bar 223 strikes astationary pin 228 to align the total signal type on bar 223 at theprinting line. Bar 223 will be restored to the latched non-printingposition by bar 68 at the end of the machine cycle.

Zero elimination on totals As thus far described, the type bars 60 whenreleased by plate 94 on total taking operations will all move to the 0position resulting in the printing of non-significant zeros in thehigher denominational orders. However, mechanism controlled jointly bythe register wheels 183 and the cam follower 212 when shifted to totaltaking position will cause elimination of such nonsignificant zeros. Asshown in Figures 2 and 7, a lever 229 is pivoted On a stud 230 in wall19 and is tensioned counterclockwise by a spring 231 to bring aninclined front end 232 into engagement with the cam follower 212.

Pivoted on a shaft 233 fixed in bracket of the register are levers 235,one for each numeral wheel 183 except the two of lowest denomination,each lever 235 having an upper end in engagement with a notched collar236 secured to a numeral wheel 183 and a rear end having a bent olf ear237 and a shoulder 239. The ears 237 overlap to the left so that anylever 235 which does not engage in the notch of collar 236 and isthereby prevented from dropping counterclockwise will hold up all levers235 to the right. As the notches of collars 236 are in position underthe arms of levers 235 only when the numeral wheel stands at 0, it willbe clear that only the levers 235 associated with the denominationalorders standing at nonsignificant zeros are free to drop. When any lever235 does drop the shoulder 239 thereon engages in a notch 240 of theassociated type bar 60 and prevents movement of the type bar to the 0printing position.

The levers 235 are held up to free all bars 60 during adding cycles byan ear 241 on the rear end of lever 229 which ear lies under car 237 ofthe leftmost lever 235 and so long as the lever 229 is in the Figure 7position will hold all levers 235 in the non-rack engagingposition. Whenthe total key 47 is depressed and cam follower 212 shifts to the left,Figure 7, lever 229 is permitted to rock to release ears 237 and permitsuch levers 235 as are aligned with the notches in collars 236 and arenot held up by a higher lever 235 to lock their rack bars in their homepositions. A stop 243 is secured to frame'178 to 9 prevent excessiveupward movement of the rightmost lever 235.

There are no levers 235 for the two right hand type bars 60 and thesebars are thus free when a total is taken from a clear register to moveto at least the position thus printing .00 to indicate that the registerwas clear when the total was taken.

The above description of the preferred embodiment of my invention is notto be taken in a limiting sense as substantial modifications andvariations of structure are possible without departure from theinvention as set forth in the following claims.

What is claimed is:

1. in an adding machine of the class described having a plurality ofnumeral keys, a shiftable pin carriage having settable pins therein tobe indexed by said keys, a register, amount entering means controlled bysaid pin carriage and machine cycling mechanism, the combination of arestoring arm connected to said pin carriage, a swingable member drivenby said cycling mechanism and engageable with said restoring arm torestore said pin carriage to a home position, an item repeat key, alever operated by said repeat key and latchable in an operated position,said lever moving said swingable member to a non-engaging position withrespect to said restoring arm, and engageable extensions on saidswingable member and said lever to enable said swingable members to movesaid lever to an unlatching position during a machine cycle.

2. In an adding machine of the class described having a plurality ofnumeral keys, a shiftable pin carriage having settable pins therein tobe indexed by said keys, a register, amount entering means controlled bysaid pin carriage and machine cycling mechanism, the combination of apivotal restoring arm connected to said pin carriage, a swinging platerotatable and slidable on the pivot of said restoring arm and yieldablyurged into engagement with said arm, a cam included in said cyclingmechanism to operate said swinging plate in each machine cycle, a repeatkey, a lever operated by said repeat key to slide said swingable plateto a non-operating position with respect to said restoring arm, astationary part, said lever when operated being engageable with saidstationary part to hold said lever and said swinging plate in theoperated positions, and engaging members on said lever and said swingingplate to move said lever away from said stationary part to a restoringposition during a machine cycle.

3. In an adding machine of the class described having a plurality ofnumeral keys, a shiftable pin carriage having settable pins therein tobe indexed by said keys, a register, amount entering means controlled bysaid pin carriage and machine cycling mechanism, the combination of arestoring arm to return said pin carriage to a home position, acyclically operated swinging plate normally engaged with said restoringarm, a manipulable member, a lever operable thereby, and means to locksaid lever in an operated position, said lever engaging said swingingplate to move said plate to an ineffective position with respect to saidrestoring arm and said swinging plate when operated moving said lever toan unlocked position.

4. An adding machine of the class described having a plurality ofnumeral keys, a register, ctuators for said register, indexable meanscontrolled by said numeral keys for controlling movement of saidactuators, cycling means for moving and restoring said actuators duringa cycle of said cycling means, an arm rockable to restore said indexablemeans to a non-indexed condition, a swingable plate coaxially supportedwith said arm and cyclically driven by said cycling means to rock saidarm, an item repeat key and means operated thereby to axially move saidswingable plate to an inefiective position with respect to said arm.

5. An adding machine as set out in claim 4 including a latchingmechanism to hold said repeat key operated means in an operatedposition, and cooperative parts on said swingable plate and said lastmeans to release said means from said latching mechanism when said plateis driven by said cycling means.

6. An adding machine as set out in claim 4 including a device engageableby said repeat key operated means when operated to hold said means ineffective position, a resilient means to urge said means into engagementwith said device and cooperative parts on said swingable plate and saidmeans to cyclically move said repeat key operated means out ofengagement with said device for restoration to normal position duringthe first cycle in which said repeat key is not retained depressed.

References Cited in the file of this patent UNITED STATES PATENTS1,180,556 Wetmore Apr. 25, 1916 1,426,710 Brown Aug. 22, 1922 1,851,401Munzer Mar. 29, 1932 2,021,618 Sundstrand Nov. 19, 1935 2,062,963Benninger Dec. 1, 1936 2,158,142 Muller May 16, 1939 2,194,270Sundstrand Mar. 19, 1940 2,203,533 Landsiedel June 4, 1940 2,221,861Butler Nov. 19, 1940 2,264,582 Petit Dec. 2, 1941 2,580,031 LiljestromDec. 25, 1951 2,682,371 Benninger June 29, 1954

